(2015) 200+ Treadwear Autocross Street Tire Thread

[King Tut]

So the Kumho V720s are finally available. The brand new Viper ACR was just released today and while its competitors are all rocking the Michelin Pilot Sport Cup 2s or the Pirelli P-Zero Corsas, it is coming with a set of specially designed ACR Kumho V720s. They seem to think this tire is pretty damn quick. I look forward to reading some reviews on these as I was a big fan of the Kumho XS and used them throughout my time doing HPDEs.

[scirocco78]

If I were ready to buy some Bridgestones right now, what size whould I get for my CS FRS?

[xwd]

Originally Posted by renfield90

Greg Reno? Is he a contract driver for Kumho? He had them way early...

Yes he had an early set from Kuhmo. I don't think he's a "contract" driver because Kuhmo hasn't had a competitive autocross tire in many years. His results were not all that great but I don't think he got as many runs as he wanted.

I think the 720 will be a good cheap performance tire, it seemed to be on par with the Z2* and RS3, but I don't think it will be at the level of the RE-71 or Rival-S.

[Kostamojen]

Originally Posted by scirocco78

If I were ready to buy some Bridgestones right now, what size whould I get for my CS FRS?

Should

[scirocco78]

An Engrish lesson wont' help me go faster.

[King Tut]

Originally Posted by scirocco78

An Engrish lesson wont' help me go faster.

Dats what the RE-71Rs are for.

[Dave-ROR]

Man you autocrossers are serious biznezz.

[Jawnathin]

Originally Posted by scirocco78

If I were ready to buy some Bridgestones right now, what size whould I get for my CS FRS?

Since no one else elected to be helpful, maybe I can be.

Stock wheel offsets = 225/45/17
+42 offsets (like RPF1s) = 245/40/17 or 235/45/17 (width vs taller gear, you pick)

I run 245/40s on my +42 RPF1s. I really want a 235/40, but they don't make it.

235/45/17 might fit on the stock wheel offset, but I'm not 100% sure if clear the spring or perches without any rubbing.

[rx3]

Originally Posted by 7thgear

Last year i ran on R1Rs and won two sets via contingency, so I'm sitting on quite a bit of rubber...and will probably continue to run the R1R this year (still competitive enough to get another set, or maybe a 2nds place coupon towards toyo tires)

For those than ran the R1Rs in the past, how do you feel they measure up to the new Bridgestones?

FWIW, Here's one guy saying that the Yoko A048 was significantly faster than the Bridgestone: http://www.tirerack.com/tires/tires....onsumerReviews

I've been mostly running on Toyo R888 and so far none of the competitors on Yoko A048 have been faster (granted there weren't that many, since they are somewhat pricey).
I've been running on R1R too and they weren't significantly slower than the R888. So, my conclusion would be that the Bridgestone RE71 are slower than the R888 and probably not faster than the R1R.

[vroom4]

I'll be benchmarking the r1r vs the stones here in a month or so. Probably in a damp environment.

[tahdizzle]

Originally Posted by rx3

FWIW, Here's one guy saying that the Yoko A048 was significantly faster than the Bridgestone: http://www.tirerack.com/tires/tires....onsumerReviews

I've been mostly running on Toyo R888 and so far none of the competitors on Yoko A048 have been faster (granted there weren't that many, since they are somewhat pricey).
I've been running on R1R too and they weren't significantly slower than the R888. So, my conclusion would be that the Bridgestone RE71 are slower than the R888 and probably not faster than the R1R.

That was in tracking in a corvette. In that same review he says they are great autocross tires.

Pretty much he says (its better to use an R comp for track then using the re71r)

[tahdizzle]

Originally Posted by vroom4

I'll be benchmarking the r1r vs the stones here in a month or so. Probably in a damp environment.

What sizes are you testing?

[Rampage]

There is a comparison by Andy Hollis in the GRM June edition. There is also a Podcast where they talk about the testing.

http://classicmotorsports.com/media/...t_tiretest.mp3

[scirocco78]

Originally Posted by Jawnathin

Since no one else elected to be helpful, maybe I can be.

Stock wheel offsets = 225/45/17
+42 offsets (like RPF1s) = 245/40/17 or 235/45/17 (width vs taller gear, you pick)

I run 245/40s on my +42 RPF1s. I really want a 235/40, but they don't make it.

235/45/17 might fit on the stock wheel offset, but I'm not 100% sure if clear the spring or perches without any rubbing.

Thanks!
I'm running Kosei's with 5mm spacers and 235/45 dunlops right now. The gearing bump has been worth it at my local venue.
My only concern when playing with the numbers from the Tirerack site is the tread width difference between the stones and the Dunlops. One full inch narrower on the stones? Tirerack says they measure the tread width them selves too.